Can't open apps due to Too many open files

[Joe Littlejohn]

Occasionally I find that I can't launch a new terminal, or can't achieve some other desktop task. Checking journalctl I see error messages like this:

May 15 12:12:15 jl-XPS-13-9360 terminator.desktop[11840]: dbus.exceptions.DBusException: org.freedesktop.DBus.Error.LimitsExceeded: Failed to determine seats of user "1000": Too many open files

or this:

May 15 12:12:47 jl-XPS-13-9360 google-chrome.desktop[28308]: [28308:28343:0515/121247.966786:ERROR:bus.cc(394)] Failed to connect to the bus: Failed to determine seats of user "1000": Too many open files

At the time this happen's I'm usually running Slack, Chrome, Emacs, and a few Java apps.

I'm using Ubuntu Bionic (18.04), 4.15.0-20-generic x86_64, vanilla gnome-shell.

[dino99 (9d9)]

Related question:

https://askubuntu.com/questions/162229/how-do-i-increase-the-open-files-limit-for-a-non-root-user

[Joe Littlejohn (joelittlejohn)]

Thanks @dino99. I've seen a lot of different suggestions for tackling this error, so it would be good to understand exactly which config change is the critical one.

I think this is a major bug on a newly installed system. As an Ubuntu Desktop user I shouldn't be experiencing an issue where the OS stops me from launching any new app once I have a few apps open. I shouldn't need to go hunting through logs to and start googling for a solution, then modify open file limits, just to run a handful of desktop applications.

[dino99 (9d9)]

Maybe some days Dbus will grab some builtin IA to increase/decrease ulimit on the fly !!!
But yes special user's case also need custom user settings. Not a real bug per se, but more of a wish !!!!

[Joe Littlejohn (joelittlejohn)]

I think there's a strong argument that the default max open files for Ubuntu Desktop should be higher than it is now. Modern apps use a lot of file handles.

[Joe Littlejohn (joelittlejohn)]

I tried the following:

echo '* hard nofile 65535' | sudo tee -a /etc/security/limits.conf
echo '* soft nofile 65535' | sudo tee -a /etc/security/limits.conf
echo 'session required pam_limits.so' | sudo tee -a /etc/pam.d/common-session

then restarted.

This did not fix the issue. So that's one 'increase limits' strategy we can rule out - it doesn't work for this particular problem.

[Launchpad Janitor (janitor)]

Status changed to 'Confirmed' because the bug affects multiple users.

[Joe Littlejohn (joelittlejohn)]

Not sure which part of this fixes the problem, but I don't have any issues after I run the following:

echo '* hard nofile 2097152' | sudo tee -a /etc/security/limits.conf
echo '* soft nofile 2097152' | sudo tee -a /etc/security/limits.conf
echo 'root hard nofile 2097152' | sudo tee -a /etc/security/limits.conf
echo 'root soft nofile 2097152' | sudo tee -a /etc/security/limits.conf
echo 'session required pam_limits.so' | sudo tee -a /etc/pam.d/common-session
echo 'DefaultLimitNOFILE=2097152' | sudo tee -a /etc/systemd/user.conf
echo 'DefaultLimitNOFILE=2097152' | sudo tee -a /etc/systemd/system.conf

Maybe it's all needed. Maybe only the last two lines are needed.

¯\_(ツ)_/¯